Modern telecommunications technology and standards enable communications in many different frequency ranges. Combination antennas enable transmitting and receiving with one antenna in a wide frequency range, from low frequencies up to high frequencies. Combination antennas can be used e.g. for maintaining a number of different telecommunication contacts, as a transmitter antenna and receiver antenna of many different systems, or as a jamming transmitter e.g. in military applications. Combination antennas comprise different antenna parts for different frequency ranges. Combination antennas can be used e.g. in fixed installation sites or as antennas to be fixed to vehicles.
Various combination antennas are presented in prior art. One prior-art combination antenna is presented in patent publication U.S. Pat. No. 7,339,542. The patent presents an antenna system, which is formed from one pipe-shaped antenna structure, which comprises an asymmetric dipole, which is supplied from a bicone-dipole. The bicone-dipole covers high-frequency ranges and the asymmetric dipole covers intermediate frequency ranges. The solution of the publication also presents the fact that the two dipoles described above together form a structure that operates as an antenna of a low frequency range.
A problem of prior-art antennas is that their structure does not enable a good radiation efficiency. Another problem of prior art is that combination antennas are large in size and the whole structure of the antenna cannot be made a part of a radiator. One of the problems of prior-art combination antennas to be formed from a number of antenna parts is also that the supply cable of one antenna part interferes with the operation of the other antenna part.